Ignition apparatus



' May 25, 1937. f E. laA NowslELsKl 2,031,501

IGNITION APPARATUS y Filed July 25, 1955 INVENTOR. I frz/wam? D. /VowoS/e/s/w I TTORNEY Patented May 25, 1937 UNITED STATES PATENT OFFICE IGNITION APPARATUS Edward B. Nowosielski, Bloomeld, N. J., assignor to Eclipse Aviation Corporation, East Orange, N. J a corporation of New Jersey Application lJuly 25, 1935, Serial o. 33,1.84

3 Claims.

An object of the invention is to provide a spark` plug of the type described wherein the sparking point may be kept within a suitable temperature range and excessive heat rapidly dissipated. In this connection a feature or the invention is the provision of air circulating means in two distinct regions in the plug assembly, one oi which regions of air circulation operates to supplement the other and, in conjunction therewith, achieve the stated objective.

These and other'objects will appear more fully in the detailed description of the invention which follows. Although only one embodiment of the present invention is illustrated in the accompanyingk drawing, it is to be expressly understood that this drawing is for the purpose of illustration only and is not to be construed as a limita-- tion of the scope or" the invention, reference being had for this purpose to the appended claims.

lin the drawing there is shown a transverse vertical sectional view through a device embodying the invention. Referring in detail to the drawing, reference character 5 designates the body portion oi the spark plug, the said body portion being provided with the usual threaded portion f5 for engagement with the engine housing to form the return circuit of the current which jumps across from the central electrode l to the grounded electrode A3 secured to the shell ii in any suitable manner, as by providing the shell with an inwardly turned rim 0 on which insulator against the shoulder portion I4 of the shell, a seal against escape or entry of fluid being effected at these two points by the provision of the usual gaskets I5 and I6 engaging the parts III and I3 respectively and also engaging the oppositely facing shoulders I8 and I9 of the insulator I2. Between these shoulders I8 and I9 the insulator is peripherally grooved, as indicated at 2I, and is also internally threadedl as indicated atA 22, the grooves 2I being adapted to cooperate with the radial apertures 24 in the shell 5 to establish a path for the cirulation of a cooling cur- (Ci. 12S-169) rent of air, and the threads 22 being adapted to cooperate with corresponding threads on a metallic sleeve 28 of copper or other material having good heat conducting qualities, whereby a substantial amount of heat may be taken from the electrode l along this region and transferred through the insulator, to be dissipated along the surfaces of the grooves 2I, or radiated along the upper annular chamber 29 constituting a part of the second region oi air circulation now to be described.

chamber 29 of the insulator for a considerable distance, there is an additional area of heat conducting surface from which the heat may be radiated, and thus the removal of heat from the electrode and terminal member is accelerated, and the heat thus removed, which is in addition to the heat removed along the region contacted by the copper sleeve 28 and the 1lower` endo! the insulator I2, serves to establish a decided heat differential or temperature gradient along the length of the electrode. The result is that relatively little heat finds its way past the terminal cap 33, and in this manner the cable and connections to the said cap are maintained at a temperature below that which would be injurious. As a further heat controlling factor, a washer 36 of heat resisting material, such as asbestos, may be inserted between cap 33, and the corei.

Annular member Il, interposed between electrode 8 and the inner shoulder of the shell, serves a double purpose. It acts as a baffle as well as a heat dissipator, transferring heat from the electrode 8 to the shell by virtue of its broad surface /contact with both these parts.

gaskets l5 and IB, renders the plug air and gas tight.

What is claimed is:

1. In a spark plug, an insulator provided with an annular chamber centrally thereof, a second annular chamber extending below said rstnamed chamber and separated therefrom by the interposition of said insulator, and means for facilitating circulation of separate air currents in each of said chambers.

2. In a. spark plug, an insulator provided with an annular chamber centrally thereof, a second annular chamber extending below said firstnamed chamber and separated therefrom by the interposition of said insulator, and means for facilitating circulation of separate air currents trode extending through said chamber, a terminal member engaging one end of said electrode and dening the upper limit of said chamber, and means dening the lower limit of said cham ber, said means including an insulator supporting said terminal member, and a metallic sleeve adjustably engaging said insulator.

EDWARD B. NOWOSIELSIU. 

